Palestinian Hamas police officers stand next to the bodies of Hamas gunmen, who were killed in an explosion, at a hospital morgue in the central Gaza Strip May 5, 2018. REUTERS/Ibraheem Abu Mustafa.

An explosion in Gaza killed six Hamas gunmen on Saturday, the group said. It blamed the incident on Israel, which declined comment.

A statement from the Palestinian Islamist terror group called the incident a “deplorable Zionist crime” perpetrated against its fighters.

“During a complicated security and intelligence operation conducted by Qassam Brigades to investigate a serious and a grave security incident conducted by the Zionist enemy against Palestinian resistance, a deplorable crime took place against our Mujahideen in the area of Zawayda in central Gaza Strip,” it said.

Reuters television captured a pillar of smoke rising above the village of Zawayda near the coast of Gaza, far from the border with Israel where tensions have escalated in recent weeks.

The exact circumstances of the blast were unclear and Hamas, which controls the Gaza Strip, provided no further details.

An Israeli military spokesman declined to comment on the incident, although a more junior official had earlier denied the army was involved.

Israel and the West designate Hamas as a terrorist organization.

Israel withdrew its troops and settlers from Gaza in 2005. But, citing security concerns, Israel maintains a naval blockade of the coastal territory, keeping some restrictions on the movement of Palestinians and goods across the frontier.

Egypt, battling an Islamist insurgency in neighboring Sinai, keeps its border with Gaza largely closed.

Forty-three Palestinians — many of whom have been identified as members of terror groups — have been shot and killed by Israeli forces since March 30, when Gazans began weekly protests dubbed “The Great March of Return” along the border with Israel.

Facing censure over its use of live fire in the protests, Israel says it is protecting its border and takes such action only when protesters, some hurling fire-bombs and trying to plant explosives, come too close.

Israel says Hamas is using the protests as cover to try to carry out attacks. Hamas denies the accusation.